Result of cross-matching the Xue et al. (2008) reference dataset with Gaia DR2. Upper panel: Xue et al. (2008) objects plotted as turquoise dots on the Gaia DR2 colour-magnitude diagram exhibiting a large scatter in absolute magnitude due to incorrect parallax measurements. Those with parallax error < 20% are plotted as red large dots. Lower panel: Lindegren et al. (2018) ‘clean subset selection C’ (black) compared with Xue et al. (2008) objects with parallax error < 20% (red) on the same scales as the upper plot in the Gaia DR2 colour-magnitude diagram.